net: ipv4: Move ip_options_fragment() out of loop

stable inclusion
from stable-v5.10.96
commit 2f56c4845df93c509ea3a63588fd4251ef5c5c87
bugzilla: https://gitee.com/openeuler/kernel/issues/I55NWB

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=2f56c4845df93c509ea3a63588fd4251ef5c5c87

--------------------------------

[ Upstream commit faf482ca ]

The ip_options_fragment() only called when iter->offset is equal to zero,
so move it out of loop, and inline 'Copy the flags to each fragment.'
As also, remove the unused parameter in ip_frag_ipcb().
Signed-off-by: NYajun Deng <yajun.deng@linux.dev>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>
Signed-off-by: NSasha Levin <sashal@kernel.org>
Signed-off-by: NYu Liao <liaoyu15@huawei.com>
Reviewed-by: NWei Li <liwei391@huawei.com>
Signed-off-by: NZheng Zengkai <zhengzengkai@huawei.com>

net/ipv4/ip_output.c

@@ -614,18 +614,6 @@ void ip_fraglist_init(struct sk_buff *skb, struct iphdr *iph,
 }
 EXPORT_SYMBOL(ip_fraglist_init);
 
-static void ip_fraglist_ipcb_prepare(struct sk_buff *skb,
-				     struct ip_fraglist_iter *iter)
-{
-	struct sk_buff *to = iter->frag;
-
-	/* Copy the flags to each fragment. */
-	IPCB(to)->flags = IPCB(skb)->flags;
-
-	if (iter->offset == 0)
-		ip_options_fragment(to);
-}
-
 void ip_fraglist_prepare(struct sk_buff *skb, struct ip_fraglist_iter *iter)
 {
 	unsigned int hlen = iter->hlen;
@@ -671,7 +659,7 @@ void ip_frag_init(struct sk_buff *skb, unsigned int hlen,
 EXPORT_SYMBOL(ip_frag_init);
 
 static void ip_frag_ipcb(struct sk_buff *from, struct sk_buff *to,
-			 bool first_frag, struct ip_frag_state *state)
+			 bool first_frag)
 {
 	/* Copy the flags to each fragment. */
 	IPCB(to)->flags = IPCB(from)->flags;
@@ -845,12 +833,13 @@ int ip_do_fragment(struct net *net, struct sock *sk, struct sk_buff *skb,
 
 		/* Everything is OK. Generate! */
 		ip_fraglist_init(skb, iph, hlen, &iter);
+		ip_options_fragment(iter.frag);
 
 		for (;;) {
 			/* Prepare header of the next frame,
 			 * before previous one went down. */
 			if (iter.frag) {
-				ip_fraglist_ipcb_prepare(skb, &iter);
+				IPCB(iter.frag)->flags = IPCB(skb)->flags;
 				ip_fraglist_prepare(skb, &iter);
 			}
 
@@ -905,7 +894,7 @@ int ip_do_fragment(struct net *net, struct sock *sk, struct sk_buff *skb,
 			err = PTR_ERR(skb2);
 			goto fail;
 		}
-		ip_frag_ipcb(skb, skb2, first_frag, &state);
+		ip_frag_ipcb(skb, skb2, first_frag);
 
 		/*
 		 *	Put this fragment into the sending queue.